A digital copier which processes digitized image data from an analog copier is known. Further, a digital composite apparatus exists which combines the various functions including a facsimile, printer and a scanner in addition to the functions of a copier.
FIG. 22 is a block diagram showing a hardware configuration of such a digital composite apparatus according to the conventional art. As shown in FIG. 22, the digital composite apparatus comprises a section (copier section) constituting a copier configured with a series of component units including a read unit 2201, an image processing unit 2202, a video control unit 2203 and a write unit 2204, together with a memory control unit 2205 and a memory module 2206, to which a facsimile control unit 2212, a printer control unit 2213 and a scanner control unit 2214 or the like are additionally connected through a motherboard 221, thereby realizing the various functions of a digital composite apparatus.
In the copier section which realizes the function of a copier, a series of operation of the component units including the read unit 2201, the image processing unit 2202, the video control unit 2203 and the write unit 2204 is controlled by a system controller 2207, a RAM 2208 and a ROM 2209. The units including the facsimile control unit 2212, the printer control unit 2213 and the scanner control unit 2214, realize the functions thereof by utilizing part of the series of operation established in the copier.
In other words, the function of a digital composite apparatus is realized by adding the facsimile control unit 2212, the printer control unit 2213 and the scanner control unit 2214 to the copier section established as a system including the series of component units. This configuration is employed against the background of emphasizing (increasing) the processing speed by configuring the series of the component unit with the ASIC (Application Specific Integrated Circuit) hardware or the like.
An “image processing apparatus” (Japanese Unexamined Patent Application Laid-Open No. 8-274986, for example) is disclosed which performs the image processing of the read signal, the image accumulation in a memory, the concurrent operation of a plurality of functions and the optimization of the respective image processing. This apparatus can execute various image processing with a single image processing configuration.
In the digital composite apparatus according to the conventional art, however, the copier section is established as a system. Thus, there is a disadvantage that each of the unit connected to the copier section such as the facsimile control unit 2212, the printer control unit 2213 and the scanner control unit 2214 requires a system independent of the copier section if the respective functions thereof are to be realized.
Each of these unit is required to have a memory module of its own for realizing the function thereof. Each unit cannot effectively utilize the memory module 2206 of the copier section. Therefore, size and cost of the apparatus are disadvantageously increased due to the provision of a memory module for each unit.
Since the copier section is established as one system, there was the problem that the function cannot be efficiently improved in keeping with the performance improvement of the peripheral units. In the case where it is desired to change only the read unit 2201 and the write unit 2204, or more specifically, it is desired to change the read unit 2201 of 400 dpi or the write unit 2204 of 400 dpi to those of 600 dpi, the function of the whole apparatus cannot not be easily improved by merely replacing a unit.
In view of the fact that a system of the whole copier has already been established to read/write data with 400 dpi, the proposed change of the unit described above requires a corresponding change of the matrix size and the threshold value for intermediate processing. Also for other units, the setting may be required to be changed to permit to read/write operation with 600 dpi.
In the case where the apparatus is composed of a hardware configuration such as ASIC, therefore, the hardware itself (customized IC or LSI or the like) must be replaced. With the performance improvement of the peripheral units, the mere replacement of the peripheral units cannot easily make it possible for the apparatus to exhibit its functions.
These problems are not confined to the peripheral units but may be encountered similarly when attempting to improve the function such as the operability of the digital composite apparatus. In other words, for improving the function of the digital composite apparatus, the work of changing the whole system is required. The resulting problem is that not only the designer cannot easily improve the function of the digital composite apparatus but also the latest algorithm cannot be readily provided to the users of the digital composite apparatus.
Moreover, since the copier section is established as one system, the problem is that the functions cannot be easily segmented when using the digital composite apparatus as a scanner unit or a printer unit.
As described above, the conventional composite apparatus having the problem that the optimum control configuration is not attained from the view point of assuring the effective utilization of each resources including the sharing of a module, the improvement of the function by replacing individual units and the segmentation of a plurality of functions or the like.